[WIP] Subclassing OpenSim classes in Python

Bindings/Python/__init__.py

@@ -31,3 +31,37 @@
 geometry_path = os.path.join(curFolder, 'Geometry')
 if os.path.exists(geometry_path):
     ModelVisualizer.addDirToGeometrySearchPaths(geometry_path)
+
+import copy
+
+# TODO consider moving this to the interface files.
+def declare_concrete_object(original_class):
+    """This method should be used as a decorator to achieve the similar
+    behavior as the C++ OpenSim_DECALRE_CONCRETE_OBJECT macro.
+
+    """
+
+    # Add abstract methods.
+    def getConcreteClassName(self):
+        return original_class.__name__
+    def clone(self):
+        # TODO this implementation is incorrect!
+        print "DEBUG", type(original_class().__disown__()), "ENDDEBUG"
+        #print "DEBUG", type(copy.deepcopy(self)), "ENDDEBUG"
+        #return None
+        #return copy.deepcopy(self) #None
+        obj = self.__class__()
+        obj._markAdopted()
+        #return obj #original_class().__disown__()
+        return original_class().__disown__()
+
+    original_class.getConcreteClassName = getConcreteClassName
+    original_class.clone = clone
+
+    # TODO getClassName()
+    # TODO safeDownCast()
+    # TODO Self
+    # TODO Super
+
+    return original_class
+

Bindings/Python/swig/python_common.i

@@ -66,6 +66,15 @@ using namespace SimTK;
 //    }
 //}
 
+// Directors
+// =========
+%feature("director") OpenSim::Object::clone; 
+%feature("director") OpenSim::Object::getConcreteClassName; 
+%feature("director") OpenSim::Component;
+
+// Rename
+// ======
+
 %rename(printToXML) OpenSim::Object::print(const std::string&) const;
 %rename(printToXML) OpenSim::XMLDocument::print(const std::string&);
 %rename(printToXML) OpenSim::XMLDocument::print();

Bindings/Python/swig/python_simulation.i

@@ -44,6 +44,16 @@ using namespace SimTK;
     }
 }
 
+// Directors
+// =========
+%feature("director") OpenSim::Analysis;
+// TODO quick way to allow printing to XML.
+%feature("nodirector") OpenSim::Analysis::updateXMLNode;
+%feature("director") OpenSim::ModelComponent;
+%feature("nodirector") OpenSim::ModelComponent::updateXMLNode;
+// This is a `final` method, and SWIG doesn't know to avoid them for directors.
+%feature("nodirector") OpenSim::ModelComponent::extendConnect;
+
 // Rename
 // ======
 

Bindings/Python/tests/test_extending_classes.py

@@ -0,0 +1,161 @@
+"""Subclassing OpenSim classes in python Using SWIG director classes.
+
+"""
+
+import os
+import unittest
+
+import opensim as osim
+import copy
+
+test_dir = os.path.join(os.path.dirname(os.path.abspath(osim.__file__)),
+                        'tests')
+
+class MyAnalysis(osim.Analysis):
+    def begin(self, state):
+        print("BEGIN!!!!")
+        self.test_begin = 61
+        return 1
+    def step(self, state, stepNumber):
+        print("STEP!!!!")
+        self.test_step = 51
+        return 1
+    def end(self, state):
+        print("END!!!!")
+        self.test_end = 37
+        return 1
+    def clone(self):
+        # this's wrong sinc no cloning is done but seems unrelated to SWIG wiring
+        print("CLONING!")
+        return self
+    def getConcreteClassName(self):
+        print("in getConcreteClassName")
+        return "MyAnalysis"
+
+
+@osim.declare_concrete_object
+class MyModelComponent(osim.ModelComponent):
+    def __init__(self):
+        super(MyModelComponent, self).__init__()
+    def extendAddToSystem(self, *args, **kwargs):
+        print("DEBUG!!!!")
+        self.addStateVariable("funstate")
+        print("DEBUG????")
+
+class TestExtendingClasses(unittest.TestCase):
+    def test_analysis_forward_adopt(self):
+        # Adopt the analysis and run the ForwardTool.
+        model = osim.Model(os.path.join(test_dir, "arm26.osim"))
+        state = model.initSystem()
+        myanalysis = MyAnalysis()
+        myanalysis.setModel(model)
+        myanalysis.setName('my_analysis')
+
+        # Add our python subclass to the model.
+        model.getAnalysisSet().adoptAndAppend(myanalysis)
+
+        # Simple tests.
+        analysis = model.getAnalysisSet().get(0)
+        assert analysis.getConcreteClassName() == 'MyAnalysis'
+        analysis.begin(state)
+
+        # Run tool.
+        forward = osim.ForwardTool()
+        forward.setModel(model)
+        forward.run()
+        print("TOOL RAN SUCCESSFULLY!!!!")
+        # Make sure that MyAnalysis was evaluated.
+        #assert analysis.test_begin == 61
+        #assert analysis.test_step == 51
+        #assert analysis.test_end == 37 # TODO fails.
+
+    def test_analysis_clone(self):
+        # Adopt the analysis and run the ForwardTool.
+        model = osim.Model(os.path.join(test_dir, "arm26.osim"))
+        myanalysis = MyAnalysis()
+        myanalysis.setName('my_analysis')
+
+        #import copy
+        #copy.deepcopy(myanalysis)
+
+        # Add our python subclass to the model.
+        model.getAnalysisSet().cloneAndAppend(myanalysis)
+
+        # Simple tests.
+        #analysis = model.getAnalysisSet().get(0)
+
+    def test_analysis_concreteclassname(self):
+        # Adopt the analysis and run the ForwardTool.
+        model = osim.Model(os.path.join(test_dir, "arm26.osim"))
+        state = model.initSystem()
+        myanalysis = MyAnalysis()
+        myanalysis.setName('my_analysis')
+
+        # Add our python subclass to the model.
+        model.getAnalysisSet().adoptAndAppend(myanalysis)
+
+        # Simple tests.
+        analysis = model.getAnalysisSet().get(0)
+        print analysis.getConcreteClassName()
+        assert analysis.getConcreteClassName() == 'MyAnalysis'
+
+    def test_analysis_forward_clone(self):
+        # Adopt the analysis and run the ForwardTool.
+        model = osim.Model(os.path.join(test_dir, "arm26.osim"))
+        state = model.initSystem()
+        myanalysis = MyAnalysis()
+        myanalysis.setName('my_analysis')
+        myanalysis.setModel(model);
+        # Add our python subclass to the model.
+        model.getAnalysisSet().cloneAndAppend(myanalysis)
+
+        # Simple tests.
+        analysis = model.getAnalysisSet().get(0)
+        assert analysis.getConcreteClassName() == 'MyAnalysis'
+        analysis.begin(state)
+
+        # Run tool.
+        forward = osim.ForwardTool()
+        forward.setModel(model)
+        forward.run()
+
+        # Make sure that MyAnalysis was evaluated.
+        assert analysis.test_begin == 61
+        assert analysis.test_step == 51
+        #assert analysis.test_end == 37 # TODO fails.
+
+    def test_registerType(self):
+        # TODO causes segfault.
+        ma = MyAnalysis()
+        ma.thisown = False
+        osim.OpenSimObject.registerType(ma) #.__disown__())
+        a = osim.OpenSimObject.getDefaultInstanceOfType('MyAnalysis')
+        assert a.getConcreteClassName() == 'MyAnalysis'
+
+    def test_printToXML(self):
+        ma = MyAnalysis()
+        ma.printToXML('test_MyAnalysis.xml')
+
+    def test_ModelComponent_addToSystem(self):
+        # Adopt the analysis and run the ForwardTool.
+        model = osim.Model(os.path.join(test_dir, "arm26.osim"))
+        mc = MyModelComponent()
+        model.addModelComponent(mc)
+        mc.extendAddToSystem()
+        state = model.initSystem()
+
+    def test_ModelComponent(self):
+        # Adopt the analysis and run the ForwardTool.
+        model = osim.Model(os.path.join(test_dir, "arm26.osim"))
+        mc = MyModelComponent()
+        model.addModelComponent(mc)
+        state = model.initSystem()
+
+        # Run tool.
+        forward = osim.ForwardTool()
+        forward.setModel(model)
+        forward.run()
+
+
+
+